Oliver 1365 power steering inoperable, sloppy control valve ball stud

My power steering is inop. When I turn the steering wheel and the drag link pushes or pulls on the cylinder control ball stud ( at the cylinder control valve assembly) it seems loose and doesn't push on the caps. Could this be from really weak Belleville springs. When I took the control valve assembly off, the ball feels loose and sloppy. It doesn't depress either cap. It seems like the ball stud should fit snug between the caps. Maybe I need a new control head or complete cylinder assembly. Any help greatly appreciated. It's very hard to drive without p/s and I need my tractor badly!